As an electronic advertising system, there is a communication system called digital signage. In this communication system, a signage terminal is allocated as a display in more than one place indoors and outdoors. A signage terminal receives and displays a message for advertisement, etc., sent from a signage server. If a user viewing a signage terminal is interested in the message, the user can, for example, read the barcode of the advertisement by means of a portable terminal and contact the provider of the advertisement via the portable terminal.
The above-described signage terminal unilaterally delivers information of advertisement, etc., to viewers via the signage terminal. In view of the present situation, there are few users of such a signage terminal.